ExamBro
ExamBro
WBJEE · Maths · Hyperbola

If the straight line \((a-1) x-b y+4=0\) is normal to the hyperbola \(x y=1\), then which of the following does not hold?

  1. A \(a>1, b>0\)
  2. B \(a>1, b < 0\)
  3. C \(a < 1, b < 0\)
  4. D \(a < 1, b>0\)
Verified Solution

Answer & Solution

Correct Answer

(C) \(a < 1, b < 0\)

Step-by-step Solution

Detailed explanation

Given equation of straight line is \[ (a-1) x-b y+4=0 \] Slope \(=-\frac{\text { Coefficient of } x}{\text { Coefficient of } y}\) \(=\frac{-(a-1)}{-b}=\frac{a-1}{b}\) Equation of hyperbola is \(x y=1\) \(\Rightarrow \quad y=\frac{1}{x}\)…